Date: Mon, 1 Mar 2004 09:19:24 +1100
From: Nathan Scott <nathans@sgi.com>
To: Michael Lampe <Michael.Lampe@iwr.uni-heidelberg.de>
Cc: linux-xfs@oss.sgi.com
Subject: Re: 2.4.25 & xfs & ide write barriers
Message-ID: <20040229221924.GA731@frodo>
References: <403E0A7A.3040505@iwr.uni-heidelberg.de>
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On Thu, Feb 26, 2004 at 04:02:18PM +0100, Michael Lampe wrote:
> fs/xfs/linux/xfs_buf.c already has
> 
>   #ifdef RQ_WRITE_ORDERED
>           if (flush)
>                  set_bit(BH_Ordered_Flush, &bufferlist[cnt-1]->b_state);
>   #endif
> 
> in _pagebuf_page_io.
> 
> Is this all I need (I already have applied the ide write barrier patch)
> to safely use disk write back caching?
> 

(which IDE write barrier patch is that, out of curiousity?)

This stuff is untested by anyone here at SGI, so YMMV.  It is
also not going to work in the presence of unwritten extents
(which were implemented after this change), some additional
code would be needed there.

cheers.

-- 
Nathan